Dear Sir or Madam,
My name is Wayne Smith and I founded the Pro-Nuclear Space Movement back in 1998 to promote nuclear powered energy and propulsion systems in space. We have had some measure of success over the years. The nuclear space initiative was cause for celebration as you can quite imagine. Over the years I've written articles and helped journalists seeking information. I even went head to head with Bruce Gagnon at SpaceDaily.com . Sometimes I worked to the point of utter exhaustion trying to help popularise nuclear space science and dispel it's myths. The turnaround in public opinion since I first started has been nothing short of staggering.
The best option for affordable manned missions to Mars and beyond is the controversial Orion concept.
The feasibility of this technology was established nearly half a century ago. It promises both high exhaust velocity and thrust. I am hoping you are open minded enough to hear me out. I realise that the word fallout conjures panic but I believe the residual radiation from a ground launch can be minimised to an acceptable level.
In the past, any amount of radiation was considered lethal but recently this assumption has been proven false. The linear non threshold method of estimating the threat from fallout has come under fire in light of research into hormesis and cellular repair.
Back in the 1960's it was estimated that an Orion launch might kill 10 people around the world from cancer. More recent calculations have revised this figure down to maybe 1 and even that calculation is questionable. This is for a launch straight off the desert floor of Nevada without any attempt to prevent contamination. It would have sucked many tons of dirt through the fireballs to become irradiated. I and other members of NuclearSpace have discussed this scenario for years and come up with many ways to reduce such fallout.
The most obvious is to use a thick metal pad 1km or more in diameter coated with a graphite based oil. Oil has special opaquing properties and steel is sufficiently resilient to suffer only millimetres of ablation. Even without an extra graphite oil coating. No dirt means no fallout. Another option is a sea launch. This idea was suggested to me by Jerry Pournelle. Airbursts do create some fallout from atmospheric dust and water vapour but not as much as legend holds.
I believe that preventing the groundburst alone would eliminate 99.99999% or more of the fallout generated. The remaining traces would gradually dissipate into the background radiation. We both know that the number one challenge for reaching Mars is getting payload off earth. Orion can reach space with almost the same mass it had on the pad. Not only is a Mars mission feasible but practical. The brilliant men who worked on this project are getting older and not everything they learned can be found in text form. Eventually they will pass on to the next world and take this invaluable knowledge with them forever.
It should be pointed out that over 1 million people died last year in automobile related incidents. Over 10,000 from coal burning. Both Thorium and Uranium exist in coal beds and this material gets burned up with the coal before being pumped into our atmosphere. By comparison an Orion launch with sensible precautions would have negligible impact.
Other ways of reducing fallout further include specially designed pulse units with radiation resistant casings. We could experiment with short lived radioisotopes too. Some only last a few hours. They would have to be placed in a pulse unit very quickly and used soon but we only need these expensive versions for the atmospheric stage. Launching vertically without an orbital trajectory would mean only a few minutes in the atmosphere.
We would only need one launch. Building big means we can carry everything necessary for decades of spaceflight. Ten thousand tons is not unreasonable. Even one hundred thousand tons is possible. In fact, the bigger you construct it, the more efficient an Orion is. Orion's can't easily land but shuttles could be taken along. The industrial infrastructure to utilise space resources too. This opens up the possibility of building more ships in space. Perhaps with asteroid materials. Larger Orions are simpler to build, can carry more payload and make it easier to shield the crew against radiation. A small bunker could be built into the infrastructure with 60cm walls. Building big also means we can use larger pulse units. Hydrogen devices are a thousand times more powerful and cleaner than fission. Yet another way fallout can be reduced.
There are other ways and I'm certain a research panel could think up more. An environmental impact study would demonstrate that a launch can be made perfectly safe. To both ensure zero risk to the surrounding area and prevent protestors from GNAWNPIS invading the launch area I would recommend launching from Antarctica. It has less atmospheric dust/water vapour to irradiate and no life exists there.
If you check the figures by computer simulation you will find the fallout produced is insignificant. I believe the public can be convinced that such a mission is worthwhile. Back in the 60's shortly after Orion was declassified some of the Orioneers were on a plane and with a captive audience they explained their objectives. The response was overwhelmingly in favour of the idea. People are individuals with the ability to make good decisions when informed enough to weigh things up rationally.
All the best,